Fill a drawn triangle using lines - c#

i need to generate a new method to fill the triangle in the below code and call it separately
any advise please?
public void draw(Graphics g, Pen blackPen)
{
double xDiff, yDiff, xMid, yMid;
xDiff = oppPt.X - keyPt.X;
yDiff = oppPt.Y - keyPt.Y;
xMid = (oppPt.X + keyPt.X) / 2;
yMid = (oppPt.Y + keyPt.Y) / 2;
// draw triangle
g.DrawLine(blackPen, (int)keyPt.X, (int)keyPt.Y, (int)(xMid + yDiff / 2), (int)(yMid - xDiff / 2));
g.DrawLine(blackPen, (int)(xMid + yDiff / 2), (int)(yMid - xDiff / 2), (int)oppPt.X, (int)oppPt.Y);
g.DrawLine(blackPen, (int)keyPt.X, (int)keyPt.Y, oppPt.X, oppPt.Y);
}
the method should take both of these arguments
public void fillTriangle(Graphics g, Brush redBrush)
{
}

Use a single function for the drawing, and for reduced complexity and consistency use a GraphicsPath object.
void DrawGraphics(Graphics g, Pen pen, Brush brush)
{
float xDiff=oppPt.X-keyPt.X;
float yDiff=oppPt.Y-keyPt.Y;
float xMid=(oppPt.X+keyPt.X)/2;
float yMid=(oppPt.Y+keyPt.Y)/2;
// Define path with the geometry information only
var path = new GraphicsPath();
path.AddLines(new PointF[] {
keyPt,
new PointF(xMid + yDiff/2, yMid-xDiff/2),
oppPt,
});
path.CloseFigure();
// Fill Triangle
g.FillPath(brush, path);
// Draw Triangle
g.DrawPath(pen, path);
}
The result is as seen below:

You just need to create an array with the dots, after that configure how the fill will be and then yes draw FillPolygon which is an entity to DrawPolygon which is just the outline.
public void draw(Pen blackPen)
{
Graphics draw = CreateGraphics();
Point[] points = new Point[6];
points[0].X = 0;
points[0].Y = 0;
points[1].X = 150;
points[1].Y = 150;
points[2].X = 0;
points[2].Y = 150;
using (SolidBrush fillvar = new SolidBrush(Color.FromArgb(100, Color.Yellow)))
{
draw.FillPolygon(fillvar, points.ToArray());
draw.DrawPolygon(Pens.DarkBlue, points);
}
}
If you want to draw the FillPolygon inside something, as with a PictureBox you just have to assign it to the Graphics draw.
Graphics draw = picturebox.CreateGraphics();
Above is just a practical illustration of how it works, take a look at your code. Missing just implement its xDiff, yiff, xMid, yMid coordinates.
public void draw(Graphics g, Pen blackPen)
{
double xDiff, yDiff, xMid, yMid;
Point[] points = new Point[6];
points[0].X = 50;
points[0].Y = 50;
points[1].X = 150;
points[1].Y = 150;
points[2].X = 0;
points[2].Y = 150;
SolidBrush varbrush = new SolidBrush(Color.FromArgb(100, Color.Yellow));
fillTriangle(g, varbrush, points);
}
You will have to pass the dots to fillTriangle and draw them in this method.
public void fillTriangle(Graphics g, Brush varbrush, Point[] points)
{
g.FillPolygon(varbrush, points.ToArray());
g.DrawPolygon(Pens.Red, points);
}

Related

Using Matrix.Rotate more than once C# Winforms

I've been trying to solve a problem I'm having with rotating an oval. The code that I'm posting works, but it's mimicking the kind of code I have to work with for real. Meaning, I can't use the OnPaint override and I'm limited to what I can do in the main code. I'm adding an oval to a graphic layer, and I need to be able to rotate, move and resize the oval. Move and resizing work flawlessly, but rotating doesn't work as I need it to.
If you click in the small box at the 9 oclock position,
the oval will rotate as expected:
The required behavior is to be able to click in the small box at the 12 oclock position, and have the oval rotate again. This does not occur. In order to get the oval to rotate again you need to click in the original 9 oclock position. What I'm really, really trying to find out is how to get the coordinates of the box at the 12 oclock position (or what ever position or location that box ends up after rotating) so that I can rotate it again. Thus far, I have been unable to figure it out. Please try and understand, I'm working with old code that was poorly written and I'm not allowed to change very much of it. What I write must integrate with what's already there. Below is the code snippet that demonstrates what I'm doing. I know I'm missing something obvious, just don't know what. Thanks.
public partial class Form1 : Form
{
int theAngle = 0;
Pen pen2 = new Pen(Color.FromArgb(255, 68, 125, 255), 4);
Pen pen3 = new Pen(Color.Green, 4);
Pen smallPen = new Pen(Color.Black, 1);
PointF center = new PointF(0, 0);
Rectangle rectangle = new Rectangle(20, 20, 100, 30);
Rectangle myRect2 = new Rectangle();
bool mouseBtnDown = false;
Graphics gw;
public Form1()
{
InitializeComponent();
this.MouseDown += mouseDown;
gw = this.CreateGraphics();
}
private void mouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
if (myRect2.Contains(e.Location))
theAngle+=90;
rotate();
}
if (e.Button == MouseButtons.Right)
{
//oval = false;
//mouseBtnDown = false;
theAngle = 0;
rectangle.X = e.X - 50;
rectangle.Y = e.Y - 15;
rectangle.Width = 100;
rectangle.Height = 30;
center.X = rectangle.Left + (0.5f * rectangle.Width);
center.Y = rectangle.Top + (0.5f * rectangle.Height);
myRect2.Size = new Size(15, 15);
myRect2.Location = new Point(rectangle.Left - 15, (rectangle.Top - (rectangle.Height / 2)) + 15);
drawstuff();
// Invalidate();
}
}
public void rotate()
{
var matrix = new Matrix();
matrix.RotateAt(theAngle, center);
gw.Transform = matrix;
drawstuff();
}
public void drawstuff()
{
gw.SmoothingMode = SmoothingMode.AntiAlias; // Creates smooth lines.
gw.DrawEllipse(pen2, rectangle);
gw.DrawRectangle(smallPen, myRect2);
}
}
You can use the Transform matrix to rotate points. So what I've done is get the 4 corner points of myRect2, rotate them using the same Transform matrix, then assign these to a rectangle. You can then use this new rectangle to check the location. I also changed the call to drawstuff() at the end of the right button click to call rotate(), this way the rotated rectangle can get updated when the ellipse is first placed, and the graphics transform angle gets updated to 0.
public partial class Form1 : Form
{
int theAngle = 0;
Pen pen2 = new Pen(Color.FromArgb(255, 68, 125, 255), 4);
Pen pen3 = new Pen(Color.Green, 4);
Pen smallPen = new Pen(Color.Black, 1);
PointF center = new PointF(0, 0);
Rectangle rectangle = new Rectangle(20, 20, 100, 30);
Rectangle myRect2 = new Rectangle();
Rectangle rotatedRect2 = new Rectangle();
bool mouseBtnDown = false;
Graphics gw;
public Form1()
{
InitializeComponent();
this.MouseDown += mouseDown;
gw = this.CreateGraphics();
}
private void mouseDown(object sender, MouseEventArgs e)
{
if (e.Button == MouseButtons.Left)
{
if (rotatedRect2.Contains(e.Location))
theAngle += 90;
rotate();
}
if (e.Button == MouseButtons.Right)
{
//oval = false;
//mouseBtnDown = false;
theAngle = 0;
rectangle.X = e.X - 50;
rectangle.Y = e.Y - 15;
rectangle.Width = 100;
rectangle.Height = 30;
center.X = rectangle.Left + (0.5f * rectangle.Width);
center.Y = rectangle.Top + (0.5f * rectangle.Height);
myRect2.Size = new Size(15, 15);
myRect2.Location = new Point(rectangle.Left - 15, (rectangle.Top - (rectangle.Height / 2)) + 15);
rotate();
//drawstuff();
// Invalidate();
}
}
public void rotate()
{
var matrix = new Matrix();
matrix.RotateAt(theAngle, center);
gw.Transform = matrix;
// Get the 4 corner points of myRect2.
Point p1 = new Point(myRect2.X, myRect2.Y),
p2 = new Point(myRect2.X + myRect2.Width, myRect2.Y),
p3 = new Point(myRect2.X, myRect2.Y + myRect2.Height),
p4 = new Point(myRect2.X + myRect2.Width, myRect2.Y + myRect2.Height);
Point[] pts = new Point[] { p1, p2, p3, p4 };
// Rotate the 4 points.
gw.Transform.TransformPoints(pts);
// Update rotatedRect2 with those rotated points.
rotatedRect2.X = pts.Min(pt => pt.X);
rotatedRect2.Y = pts.Min(pt => pt.Y);
rotatedRect2.Width = pts.Max(pt => pt.X) - pts.Min(pt => pt.X);
rotatedRect2.Height = pts.Max(pt => pt.Y) - pts.Min(pt => pt.Y);
drawstuff();
}
public void drawstuff()
{
gw.SmoothingMode = SmoothingMode.AntiAlias; // Creates smooth lines.
gw.DrawEllipse(pen2, rectangle);
gw.DrawRectangle(smallPen, myRect2);
}
}
Something to note. Drawing to the screen like this (using the form's created graphics and drawing using your own draw function) means the ellipses/rectangles are only drawn once. i.e. if you draw a few then minimize your form, when you bring it back up the ellipses will be gone. Not sure if this is what you're after or not. One way to fix this would be to draw the ellipses to a Bitmap and then in the form's Paint event this bitmap is draw to the form.

How to get XY of pictureBox1 after it has been transformed

I have a list of Points that have been drawn on pictureBox1.
pictureBox1 has been transformed.
Now, I want to get XY coordinates of the point that was drawn as I hover over any drawn point.
When I hover over the pictureBox1, I am getting the XY of the pictureBox -- not a transformed XY.
Can you help me get to the transformed XY?
Thanks
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
int height = pictureBox1.ClientSize.Height / 2;
int width = pictureBox1.ClientSize.Width / 2;
//=====
//scale
//=====
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
e.Graphics.TranslateTransform(-width, -height);
e.Graphics.ScaleTransform(2f, 2f);
//===========
//draw center
//===========
e.Graphics.DrawLine(new Pen(Color.Black, 0.5f), new Point(width - 2, height), new Point(width + 2, height));
e.Graphics.DrawLine(new Pen(Color.Black, 0.5f), new Point(width, height - 2), new Point(width, height + 2));
//===========
//draw points
//===========
foreach (var p in Points)
{
Point[] pts = new Point[] { new Point(p.X, p.Y) };
Rectangle rc = new Rectangle(pts[0], new Size(1, 1));
e.Graphics.DrawRectangle(Pens.Red, rc);
}
}
As a variation to #Vitaly's answer you can do this:
After transforming the Graphics object you can save its transformation matrix e.Graphics.Transform in a variable:
Matrix matrix = null;
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
int height = pictureBox1.ClientSize.Height / 2;
int width = pictureBox1.ClientSize.Width / 2;
//=====
//scale
//=====
e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
e.Graphics.TranslateTransform(-width, -height);
e.Graphics.ScaleTransform(2f, 2f);
matrix = e.Graphics.Transform; // save the transformation matrix!
...
This is necessary as the transfomation data are lost after the Paint event!
Note that the GraphicsState graphics.Save()&Restore() functions can't be used very well for this purpose, as it only puts the state on the stack for using it once, meaning it doesn't save these data in a persistent way.
Later you can use the Matrix and this function to either transform Points with the same matrix or reverse the transformation, e.g. for mouse coordinates:
PointF transformed(Point p0, bool forward)
{
Matrix m = matrix.Clone();
if (!forward) m.Invert();
var pt = new Point[] { p0 };
m.TransformPoints(pt);
return pt[0];
}
Now my MouseMove event shows the location both raw and re-transformed:
private void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
label1.Text = e.Location + " <-> " + transformed(e.Location, false) ;
}
And to test the forward transformation you could add this to the end of the Paint event:
e.Graphics.ResetTransform();
for (int i = 0; i < Points.Count; i++)
{
Point[] pts = new Point[] { Point.Round(transformed(Points[i], true)) };
Rectangle rc = new Rectangle(pts[0], new Size(19, 19));
e.Graphics.DrawRectangle(Pens.Red, rc);
}
This first clears all the transformations and then paints larger Rectangles at the same locations by calling the transformed function.
Note that this will also work with a rotated Graphics object. (Although the last test does not draw the larger rectangles rotated, just moved to the right locations.)
Also note that I return PointF for better precision when scaling with fractions. You can use Point.Round (or Point.Truncate) to get Point.
Do have a look the the Matrix.Elements: They contain the numbers you have used:
float scaleX = matrix.Elements[0];
float scaleY = matrix.Elements[3];
float transX = matrix.Elements[4];
float transY = matrix.Elements[5];
Finally: It is well worth studying the many methods of Matrix..!
You can create a Matrix with necessary transformations and apply it in pictureBox1_Paint(...) via MultiplyTransform(...):
https://msdn.microsoft.com/en-us/library/bt34tx5d(v=vs.110).aspx
Then you can use Matrix::TransformPoints(...) to get transformed XY

Refresh the canvas only for certain brushes

I'm trying to graph some circles and lines etc but I only want some lines to refresh on the canvas and the others not to, is there any way around this?
For example the mypen, mypen2 and mypen3, I want them to refresh on canvas but the graphics "g" a little further down I don't want to refresh, I want all the instances to show. How do I do this? Here is my code
private void drawlines()
{
canvas.Refresh();
int j = Int32.Parse(ivalue.Text);
float position1 = canvas.Width / 2;
float position2 = canvas.Height / 2;
float XX = (float)(Math.Round(position1 + Math.Sin(DegreeToRadian(j)) * 100));
float XY = (float)(Math.Round(position2 - Math.Cos(DegreeToRadian(j)) * 100));
float X2 = (position1 + XX);
float XY2 = XY;
System.Drawing.Pen myPen;
System.Drawing.Pen myPen2;
System.Drawing.Pen myPen3;
System.Drawing.Pen myPen4;
myPen = new System.Drawing.Pen(System.Drawing.Color.Red);
myPen2 = new System.Drawing.Pen(System.Drawing.Color.Blue);
myPen3 = new System.Drawing.Pen(System.Drawing.Color.Black);
myPen4 = new System.Drawing.Pen(System.Drawing.Color.Green);
System.Drawing.Graphics formGraphics = canvas.CreateGraphics();
formGraphics.DrawRectangle(myPen,XX, XY,3,3);
formGraphics.DrawRectangle(myPen2, canvas.Width / 2, XY, 3, 3);
formGraphics.DrawRectangle(myPen3, position1, position2, 3, 3);
formGraphics.DrawRectangle(myPen4, position1, XY2, 3, 3);
label1.Text = Convert.ToString(XY);
label1.Refresh();
listBox1.Items.Clear();
listBox1.Items.Add("XX=[" + XX + "] XY=[" + XY + "]");
}
private void Go_Click(object sender, EventArgs e)
{
for (int i = 0; i <= 360; i = i + 1)
{
drawlines();
int linearm = (canvas.Width / 2) - i;
ivalue.Text = Convert.ToString(i);
ivalue.Refresh();
int testx = Int32.Parse(label1.Text);
Graphics g;
g = canvas.CreateGraphics();
Pen p;
Rectangle r;
p = new Pen(Brushes.Green);
r = new Rectangle(linearm,testx, 1, 1);
g.DrawRectangle(p, r);
System.Threading.Thread.Sleep(15);
}
}
I assume you are using winforms? If so you need to change your code to work like this:
To be persistant everything need to be drawin in the Paint event and using its e.Graphics object. (This is the Golden Rule! Corollary: Never use System.Drawing.Graphics formGraphics = canvas.CreateGraphics();)
Everything you want to be drawn must be stored in Lists of classes, sufficient to hold all info you need.
If you were to draw only Rectangles in only one pen a List<Rectangle> would be enough, but for other shapes and pens you will want to create a class to hold those data.
Now you can:
Draw them all in the Paint event, iterating the List<your DrawItemClass>
Remove or set inactive those items in the List you don't want to be drawn any longer..

Mimicking this imaging effect

I am asking this question as the other one is two years old and not answered accurately.
I'm looking to replicate the PhotoShop effect mentioned in this article in C#. Adobe call it a Color halftone, I think it looks like some sort of rotated CMYK halftone thingy. Either way I don't know how I would do it.
Current code sample is below.
Any ideas?
P.S.
This isn't homework. I'm looking to upgrade the comic book effect I have in my OSS project ImageProcessor.
Progress Update.
So here's some code to show what I have done so far...
I can convert to and from CMYK to RGB fairly easily and accurately enough for my needs and also print out a patterned series of ellipses based on the the intensity of each colour component at a series of points.
What I am stuck at just now is rotating the graphics object for each colour so that the points are laid at the angles specified in the code. Can anyone give me some pointers as how to go about that?
public Image ProcessImage(ImageFactory factory)
{
Bitmap newImage = null;
Image image = factory.Image;
try
{
int width = image.Width;
int height = image.Height;
// These need to be used.
float cyanAngle = 105f;
float magentaAngle = 75f;
float yellowAngle = 90f;
float keylineAngle = 15f;
newImage = new Bitmap(width, height);
newImage.SetResolution(image.HorizontalResolution, image.VerticalResolution);
using (Graphics graphics = Graphics.FromImage(newImage))
{
// Reduce the jagged edges.
graphics.SmoothingMode = SmoothingMode.AntiAlias;
graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphics.PixelOffsetMode = PixelOffsetMode.HighQuality;
graphics.CompositingQuality = CompositingQuality.HighQuality;
graphics.Clear(Color.White);
using (FastBitmap sourceBitmap = new FastBitmap(image))
{
for (int y = 0; y < height; y += 4)
{
for (int x = 0; x < width; x += 4)
{
Color color = sourceBitmap.GetPixel(x, y);
if (color != Color.White)
{
CmykColor cmykColor = color;
float cyanBrushRadius = (cmykColor.C / 100) * 3;
graphics.FillEllipse(Brushes.Cyan, x, y, cyanBrushRadius, cyanBrushRadius);
float magentaBrushRadius = (cmykColor.M / 100) * 3;
graphics.FillEllipse(Brushes.Magenta, x, y, magentaBrushRadius, magentaBrushRadius);
float yellowBrushRadius = (cmykColor.Y / 100) * 3;
graphics.FillEllipse(Brushes.Yellow, x, y, yellowBrushRadius, yellowBrushRadius);
float blackBrushRadius = (cmykColor.K / 100) * 3;
graphics.FillEllipse(Brushes.Black, x, y, blackBrushRadius, blackBrushRadius);
}
}
}
}
}
image.Dispose();
image = newImage;
}
catch (Exception ex)
{
if (newImage != null)
{
newImage.Dispose();
}
throw new ImageProcessingException("Error processing image with " + this.GetType().Name, ex);
}
return image;
}
Input Image
Current Output
As you can see since the drawn ellipses are not angled colour output is incorrect.
So here's a working solution. It ain't pretty, it ain't fast (2 seconds on my laptop) but the output is good. It doesn't exactly match Photoshop's output though I think they are performing some additional work.
Slight moiré patterns sometimes appear on different test images but descreening is out of scope for the current question.
The code performs the following steps.
Loop through the pixels of the image at a given interval
For each colour component, CMYK draw an ellipse at a given point which is calculated by rotating the current point by the set angle. The dimensions of this ellipse are determined by the level of each colour component at each point.
Create a new image by looping though the pixel points and adding the CMYK colour component values at each point to determine the correct colour to draw to the image.
Output image
The code
public Image ProcessImage(ImageFactory factory)
{
Bitmap cyan = null;
Bitmap magenta = null;
Bitmap yellow = null;
Bitmap keyline = null;
Bitmap newImage = null;
Image image = factory.Image;
try
{
int width = image.Width;
int height = image.Height;
// Angles taken from Wikipedia page.
float cyanAngle = 15f;
float magentaAngle = 75f;
float yellowAngle = 0f;
float keylineAngle = 45f;
int diameter = 4;
float multiplier = 4 * (float)Math.Sqrt(2);
// Cyan color sampled from Wikipedia page.
Brush cyanBrush = new SolidBrush(Color.FromArgb(0, 153, 239));
Brush magentaBrush = Brushes.Magenta;
Brush yellowBrush = Brushes.Yellow;
Brush keylineBrush;
// Create our images.
cyan = new Bitmap(width, height);
magenta = new Bitmap(width, height);
yellow = new Bitmap(width, height);
keyline = new Bitmap(width, height);
newImage = new Bitmap(width, height);
// Ensure the correct resolution is set.
cyan.SetResolution(image.HorizontalResolution, image.VerticalResolution);
magenta.SetResolution(image.HorizontalResolution, image.VerticalResolution);
yellow.SetResolution(image.HorizontalResolution, image.VerticalResolution);
keyline.SetResolution(image.HorizontalResolution, image.VerticalResolution);
newImage.SetResolution(image.HorizontalResolution, image.VerticalResolution);
// Check bounds against this.
Rectangle rectangle = new Rectangle(0, 0, width, height);
using (Graphics graphicsCyan = Graphics.FromImage(cyan))
using (Graphics graphicsMagenta = Graphics.FromImage(magenta))
using (Graphics graphicsYellow = Graphics.FromImage(yellow))
using (Graphics graphicsKeyline = Graphics.FromImage(keyline))
{
// Ensure cleared out.
graphicsCyan.Clear(Color.Transparent);
graphicsMagenta.Clear(Color.Transparent);
graphicsYellow.Clear(Color.Transparent);
graphicsKeyline.Clear(Color.Transparent);
// This is too slow. The graphics object can't be called within a parallel
// loop so we have to do it old school. :(
using (FastBitmap sourceBitmap = new FastBitmap(image))
{
for (int y = -height * 2; y < height * 2; y += diameter)
{
for (int x = -width * 2; x < width * 2; x += diameter)
{
Color color;
CmykColor cmykColor;
float brushWidth;
// Cyan
Point rotatedPoint = RotatePoint(new Point(x, y), new Point(0, 0), cyanAngle);
int angledX = rotatedPoint.X;
int angledY = rotatedPoint.Y;
if (rectangle.Contains(new Point(angledX, angledY)))
{
color = sourceBitmap.GetPixel(angledX, angledY);
cmykColor = color;
brushWidth = diameter * (cmykColor.C / 255f) * multiplier;
graphicsCyan.FillEllipse(cyanBrush, angledX, angledY, brushWidth, brushWidth);
}
// Magenta
rotatedPoint = RotatePoint(new Point(x, y), new Point(0, 0), magentaAngle);
angledX = rotatedPoint.X;
angledY = rotatedPoint.Y;
if (rectangle.Contains(new Point(angledX, angledY)))
{
color = sourceBitmap.GetPixel(angledX, angledY);
cmykColor = color;
brushWidth = diameter * (cmykColor.M / 255f) * multiplier;
graphicsMagenta.FillEllipse(magentaBrush, angledX, angledY, brushWidth, brushWidth);
}
// Yellow
rotatedPoint = RotatePoint(new Point(x, y), new Point(0, 0), yellowAngle);
angledX = rotatedPoint.X;
angledY = rotatedPoint.Y;
if (rectangle.Contains(new Point(angledX, angledY)))
{
color = sourceBitmap.GetPixel(angledX, angledY);
cmykColor = color;
brushWidth = diameter * (cmykColor.Y / 255f) * multiplier;
graphicsYellow.FillEllipse(yellowBrush, angledX, angledY, brushWidth, brushWidth);
}
// Keyline
rotatedPoint = RotatePoint(new Point(x, y), new Point(0, 0), keylineAngle);
angledX = rotatedPoint.X;
angledY = rotatedPoint.Y;
if (rectangle.Contains(new Point(angledX, angledY)))
{
color = sourceBitmap.GetPixel(angledX, angledY);
cmykColor = color;
brushWidth = diameter * (cmykColor.K / 255f) * multiplier;
// Just using blck is too dark.
keylineBrush = new SolidBrush(CmykColor.FromCmykColor(0, 0, 0, cmykColor.K));
graphicsKeyline.FillEllipse(keylineBrush, angledX, angledY, brushWidth, brushWidth);
}
}
}
}
// Set our white background.
using (Graphics graphics = Graphics.FromImage(newImage))
{
graphics.Clear(Color.White);
}
// Blend the colors now to mimic adaptive blending.
using (FastBitmap cyanBitmap = new FastBitmap(cyan))
using (FastBitmap magentaBitmap = new FastBitmap(magenta))
using (FastBitmap yellowBitmap = new FastBitmap(yellow))
using (FastBitmap keylineBitmap = new FastBitmap(keyline))
using (FastBitmap destinationBitmap = new FastBitmap(newImage))
{
Parallel.For(
0,
height,
y =>
{
for (int x = 0; x < width; x++)
{
// ReSharper disable AccessToDisposedClosure
Color cyanPixel = cyanBitmap.GetPixel(x, y);
Color magentaPixel = magentaBitmap.GetPixel(x, y);
Color yellowPixel = yellowBitmap.GetPixel(x, y);
Color keylinePixel = keylineBitmap.GetPixel(x, y);
CmykColor blended = cyanPixel.AddAsCmykColor(magentaPixel, yellowPixel, keylinePixel);
destinationBitmap.SetPixel(x, y, blended);
// ReSharper restore AccessToDisposedClosure
}
});
}
}
cyan.Dispose();
magenta.Dispose();
yellow.Dispose();
keyline.Dispose();
image.Dispose();
image = newImage;
}
catch (Exception ex)
{
if (cyan != null)
{
cyan.Dispose();
}
if (magenta != null)
{
magenta.Dispose();
}
if (yellow != null)
{
yellow.Dispose();
}
if (keyline != null)
{
keyline.Dispose();
}
if (newImage != null)
{
newImage.Dispose();
}
throw new ImageProcessingException("Error processing image with " + this.GetType().Name, ex);
}
return image;
}
Additional code for rotating the pixels is as follows. This can be found at Rotating a point around another point
I've left out the colour addition code for brevity.
/// <summary>
/// Rotates one point around another
/// <see href="https://stackoverflow.com/questions/13695317/rotate-a-point-around-another-point"/>
/// </summary>
/// <param name="pointToRotate">The point to rotate.</param>
/// <param name="centerPoint">The centre point of rotation.</param>
/// <param name="angleInDegrees">The rotation angle in degrees.</param>
/// <returns>Rotated point</returns>
private static Point RotatePoint(Point pointToRotate, Point centerPoint, double angleInDegrees)
{
double angleInRadians = angleInDegrees * (Math.PI / 180);
double cosTheta = Math.Cos(angleInRadians);
double sinTheta = Math.Sin(angleInRadians);
return new Point
{
X =
(int)
((cosTheta * (pointToRotate.X - centerPoint.X)) -
((sinTheta * (pointToRotate.Y - centerPoint.Y)) + centerPoint.X)),
Y =
(int)
((sinTheta * (pointToRotate.X - centerPoint.X)) +
((cosTheta * (pointToRotate.Y - centerPoint.Y)) + centerPoint.Y))
};
}

how to make diagram fit with in panel?

hey i am trying to build a windows application in .net,i have to draw factorial image inside the panel
private void Canvas_Paint(object sender, PaintEventArgs e)
{
start_x = Canvas.Width / 2;
start_Y = Canvas.Height / 2;
for (int i = 0; i < 400; i++)
draw_T();
}
public void draw_T()
{
mypen = new Pen(Color.Green, 2F);
my_angle = my_angle + (45);
my_length = 100 + (1);
end_x = (int)(start_x + Math.Cos(my_angle * .0174539676) * my_length);
end_Y = (int)(start_Y + Math.Sin(my_angle * .0174539676) * my_length);
Point[] points =
{
new Point (start_x,start_Y),
new Point (end_x,end_Y)
};
Point[] points1 =
{
new Point ((end_x+start_x)/2,(end_Y+start_Y)/2),
new Point (end_x+50,end_Y-100)
};
start_x = end_x;
start_Y = end_Y;
Graphics g = Canvas.CreateGraphics();
g.DrawLines(mypen, points);
g.DrawLines(mypen, points1);
}
drawing T shape line,then i start to draw another T shape from last end points .But problem is diagram is going outside of the panel.How do i fix drawing inside the panel

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